Couple of Beginner Questions on RPM / Feed Rate

[GreggC]

Hey guys,
I have a Shop Fox M1049,
I want to do a finish turn on a 1.2" piece of aluminum,
I have learned I want a higher RPM spinning the piece
and a slower feed rate.
I need help with the power feed rate,
There is a 9 speed gearbox on my lathe,

Is this for feed rate speed or just for cutting threads ??
Or both ??

 

[Wreck™Wreck]

There must be another control or change gears, if change gears that is unfortunate, 9 is not nearly enough positions.

I have never used a lathe with change gears outside of the metric to inch gear which is one gear change, and I am 60 years old, do modern manufacturers of manual lathes still do that?

 

[mikey]

I looked at the manual online (https://d27ewrs9ow50op.cloudfront.net/manuals/m1049_m.pdf) and it looks like position 1 (far left hole) will give you the slowest feed rate for the gears installed already. You might check to see which gears are in place. With a 42 tooth gear in position A and a 60 tooth gear in position B, it should give you a feed rate of 0.012 inch per rev. If that is not slow enough you can always feed manually. See page 32 of your manual.

Aluminum has a cutting speed of about 200-250 SFM, which works out to a little over 600 rpm. If you put your lower belt in the BC3 position, this should give you 600 rpm which about right. See page 30 in your manual.

Does this help?

For threading, your lathe is a change gear lathe so you need to move the lever to the designated position in the chart and change the gears as shown in the diagram on the front of the lathe. This will allow the leadscrew to turn at the proper speed for the thread you're cutting and when you engage the half nut on the saddle, the saddle will move at the proper speed.

 

[GreggC]

I looked at the manual online (https://d27ewrs9ow50op.cloudfront.net/manuals/m1049_m.pdf) and it looks like position 1 (far left hole) will give you the slowest feed rate for the gears installed already. You might check to see which gears are in place. With a 42 tooth gear in position A and a 60 tooth gear in position B, it should give you a feed rate of 0.012 inch per rev. If that is not slow enough you can always feed manually. See page 32 of your manual.

Aluminum has a cutting speed of about 200-250 SFM, which works out to a little over 600 rpm. If you put your lower belt in the BC3 position, this should give you 600 rpm which about right. See page 30 in your manual.

Does this help?

For threading, your lathe is a change gear lathe so you need to move the lever to the designated position in the chart and change the gears as shown in the diagram on the front of the lathe. This will allow the leadscrew to turn at the proper speed for the thread you're cutting and when you engage the half nut on the saddle, the saddle will move at the proper speed.

Thank you Mike,
Ill change the belt to BC3 and the gearbox to #1,
This should give me a nice finish turn.

 

[GreggC]

Love this forum,
Question answered,
Problem solved in 1 hour.

 

[jlsmithseven]

Yep there are a lot of helpful and kind people here. Stick around and keep learning!

 

[Richard White (richardsrelics)]

Another "trick" is to add a small radius to the tool, as a sharp point will leave lines. The radius will cover for an improper feed rate. I machine 6061 Aluminum round stock almost daily for my tools I make, turning the OD I have like a .015 rad on the turn tool.... looks sweet

 

[GreggC]

Another "trick" is to add a small radius to the tool, as a sharp point will leave lines. The radius will cover for an improper feed rate. I machine 6061 Aluminum round stock almost daily for my tools I make, turning the OD I have like a .015 rad on the turn tool.... looks sweet

Excellent,
Thanks for the tip !!

 

[GreggC]

Hey guys,
As per the placard on my lathe the slowest feed rate
I can get is lever on position 9 with 28 tooth gear in "A"
and 60 tooth gear in "B"...yes ??
Am I interpreting this correctly ??

 

[mikey]

Yes, you are right, Gregg. My mistake - I didn't look at the placard carefully enough.